USB Connectivity
1654
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Universal Serial Bus (USB)
29.4 USB Connectivity
This section includes:
•
Transceiver interface
•
Selecting and configuring USB connectivity
•
Transceiver signaling
•
Host controller connectivity with USB transceivers
•
USB function controller connectivity with USB transceivers
•
USB hardware considerations
29.4.1 Transceiver Interface
The device provides three USB ports, two of which may be used simultaneously. In a USB system, a USB
transceiver is needed for each USB port. It converts between signaling appropriate for the USB controllers
and signaling appropriate for the USB cable. This device does not provide an integrated USB transceiver.
Several different types of external transceiver signaling are supported. Signaling between the USB
controller and the external USB transceiver for monitoring and controlling the differential USB signal is
done via a 6-wire signaling interface, with two or more additional control signals provided either by
additional signals or via an I2C link.
29.4.2 Selecting and Configuring USB Connectivity
The process of selecting desired USB connectivity and configuring the device for that connectivity can be
done using the steps listed below.
29.4.2.1 Choose the Desired USB Functionality
Choose the desired USB functionality. The USB module on this microcontroller supports the following
configurations:
•
1 USB Host Port + 1 USB Device Port, OR
•
2 USB Host Ports
Interface signals for the USB host port #2 are multiplexed with interface signals for the USB device port. If
the application requires the use of the USB device port, then the USB host port #2 must first be powered
down.
29.4.2.2 Select How USB Functionality Is Multiplexed to Pins
Refer to
for information on multiplexing and control of USB host ports and USB device port
interface signals at the top level.